Organic phosphate complexes



United States Patent O Ohio No Drawing. Filed Sept. 5, 1962, Ser. No.221,458

16 Claims. (Cl. 148-615) The present invention relates to novel organicphosphate complexes and to processes for their preparation. In a moreparticular sense, it relates to corrosion-inhibiting coatingcompositions for metal comprising the aforesaid complexes.

The corrosion of metal articles is of obvious economic significance inmany industrial applications and, as a consequence, the inhibition ofsuch corrosion is a matter of prime consideration. It is particularlysignificant to users of steel and other ferrous alloys. The corrosion ofsuch ferrous metal alloys is largely a matter of rust formation, whichin turn involves the overall conversion of the free metal to its oxide.

The theory which best explains such oxidation of ferrous metal articlespostulates the essential presence of both water and oxygen. Even minutetraces of moisture are sufiicient, according to this theory, to inducethe dissolution of iron therein and the formation of ferrous hydroxideuntil the water becomes saturated with ferrous ions. The presence ofoxygen causes the oxidation of the resulting ferrous hydroxide to ferrichydroxide, which then settles out of solution and is ultimatelyconverted to ferric oxide or rust.

The above sequence of reactions can be prevented, or at least in largemeasure inhibited, by relatively impermeable coatings which have theeffect of excluding moisture and/ or oxygen from contact with the metalsurface. Such coatings are often subjected to high humidity, corrosiveatmospheres, and physical deformation and to the extent that thesecoatings are penetrated or otherwise harmed by such influences theybecome less effective for the desired purpose. A satisfactorycorrosion-inhibiting coating then, must have the ability to resistweathering, high humidity, abrasion, deformation, and corrosiveatmospheres such as salt-laden mist or fogs, air contaminated withindustrial wastes, etc., so that a uniform protective film is maintainedupon all or most of the metal surface.

Various derivatives of acid esters of phosphoric or phosphorothioicacids have been investigated by workers engaged in the task of providingimproved protective coatings for metal. In US. Patent 2,080,299, forexample, Benning et a1. propose the treatment of ferrous metals withsimple phosphate acid esters or their alkali metal and ammonium salts toprevent rusting. Somewhat similarly, Butler and Le Suer (US. Patents2,861,907 and 2,- 820,723) find that salt-esters of certainphosphorothioic acids are effective in preventing or retarding thecorrosion of metals.

Although such known derivatives of phosphoric and phosphorothioic acidhave provided means for combating the corrosion of metals, they have notbeen completely satisfactory because of certain inherent shortcomings.The simple salt-esters of phosphoric acid are readily washed or abradedfrom a metallic surface and thus provide complete protection only in afavorable environment. The salt-esters of phosphorothioic acids, on theother hand, have the disadvantage, under certain conditions, ofdeveloping an objectionable odor reminiscent of hydrogen sulfide,particularly when a film of such a saltester comes in contact with wateror humid atmospheres.

A further disadvantage of these known derivatives of phosphoric andphosphorothioic acids is that they form oily or tacky coatings which arenot susceptible to the 3,260,622 Patented July 12, 1966 subsequentapplication of top-coats of siccative organic coating compositions suchas paint, varnish, lacquer, enamel, and the like. Thus, their use hasbeen limited to metal articles such as bulk castings, metal fasteners,fire arm parts, iron cables, etc., which do not require a dry- -filmprotective coating.

It is, therefore, a principal object of the present invention to providenovel organic phosphate complexes and processes for their preparation.

Another object is to provide corrosion-inhibiting coating compositionsfor metals, especially ferrous metals, which compositions compriseorganic phosphate complexes.

A further object is to provide novel coating compositions for metals,which compositions are resistant to weathering, abrasion, deformation,high humidity and corrosive atmospheres.

A still further object is to provide means for improving thecorrosion-inhibiting characteristics of known siccative organic coatingcompositions.

These and other objects of the invention are achieved -by providing anorganic phosphate complex prepared by the process which comprises thereaction of:

(A) one mole of a phosphorus-containing reagent selected from the groupconsisting of phosphorus pentoxide and phosphoric acids,

(B) from about 0.2 toabout 12.5 moles of a copolymer of allyl alcoholand a styrene, and

(C) from about 0.1 to about 5 moles of a compound selected from thegroup consisting of alcohols, mercaptans, amines, amides, andthioamides,

at a temperature Within the range from about 50 C. to

about 300 C. In some instances, it is desirable to have presentadditionally in the process mass from about 0.1

to about 20 moles of an alkylphenol per mole of C present.

Thin films of the organic phosphate complexes of the present inventionare remarkably effective in protecting metal surfaces, especiallyferrous metal surfaces, against the ravages of corrosion. The complexesare also useful as ingredients in known siccative organic coatingcompositions such as pa-ints, varnishes, lacquers, primers, syntheticresins, and enamels, to which compositions they impart enhancedcorrosion-inhibiting characteristics. When used for the latter purpose,a minor proportion, generally from about 0.1 to about 25 percent, of anorganic phosphate complex of this invention is blended with a majorproportion, generally from about 99.9 to about 75 percent, of asiccative organic coating composition, all parts being by weight.

REAGENT A As indicated above, the phosphorus-containing reagent A isselected from the group consisting of phosphorus pentoxide and aphosphoric acid. For reasons of convenience, economy, and reactivity inthe process of this invention, phosphorus pentoxide is generallypreferred. Where it is desired to employ phosphoric acid, any of theseveral available phosphoric acids such as polyphosphoric,orthophosphoric, metaphosphoric, or pyrophosphoric acid may be usedeither alone or in admixture as this reagent. It is also feasible to usemixtures of phosphorus pentoxide with one or more of these phosphoricacids. Phosphoric acid, if employed, will generally be the ordinarycommercial percent or 100 percent orthophosphoric acid, although moredilute acids containing at least about 25 percent H PO are also usable.

REAGENT B This reagent is a copolymer of 10 to mole-percent of allylalcohol with 90 to 10 mole-percent of a styrene. Especially useful forthe purposes of this invention are copolymers prepared fromapproximately equimolar amounts of the two monomers and having anaverage molecular weight within the range from about 500 to about 5000.

A particular preference is expressed for a copolymer of approximatelyequimolar amounts of allyl alcohol and styrene having an averagemolecular weight of about 1100-1150. Such a copolymer is availablecommercially under the trade designation, Polyol X450. Similarcopolymers of lesser or greater average molecular weight are alsoavailable commercially, including one which has an average molecularweight of about 80.

The term a styrene as used herein refers to styrene or any of varioussubstituted styrenes such :as halogensubstituted sytrenes,hydrocarbon-substituted styrenes, al-koxy-styrenes, acycloxy-styrenes,nitro-styrenes, etc. Examples of such substituted styrenes includep-chlorostyrene, p-e-thylstyrene, io-phenylstyrene, p-methoxystyrene,in-nitrostyrene, alpha-methylstyrene, and the like. In most instances,however, it is preferred to use styrene itself by reason of its lowcost, commercial availability, and excellence as a raw material in thepreparation of reagent B. v

REAGENT C The reagent is at least one compound selected from the groupconsisting of alcohols, mercaptans, amines, amides, and thioamides. Insome instances, a single reagent may contain two or more of the desiredgroups. P or example, an alkanolamine is both an alcohol and an amine.Likewise, a monothi-oglycol is both an alcohol and a mercaptan.

Alcohols useful as this reagent include both substituted andunsubstituted monohydric or polyhydric aliphatic or cycloaliphaticalcohols containing from 2 to 50 or more carbon atoms. Organic and/orinorganic substituents which may be present in the alcohols includeprincipally aromatic or heterocyclic groups such as phenyl, a-lkylphenylnaphthyl, phenanthryl, pyridyl, etc., and other groups such as chloro,bromo, cfluoro, nitro, nitroso, ether, ester, keto, sulfide, disuliide,etc. Illustrative of such alcohols are ethanol, n-propanol, isopropanol,n-butanol, isobutanol, 4-nitro-butan-old, n-pentanol, neopentanol,commercial mixtures of primary amyl alcohols, n-hexyl alcohol,4-me-thyl-pentanol2, cyclohexanol, cmetlhylcyclohexanol, alphaterpineol,n-octanol, isooctanol, capryl alcohol, 3,5,5-trimethylhexanol,n-dodecanol, cetyl alcohol, oleyl alcohol, n-oct-adecanol, cerylalcohol, alcohols derived from the oxidation of paraffin wax,tricosanol, triacontanol, hexatriacontanol, carnau-byl alcohol, ethyleneglycol, propylene glycol, diethylene glycol, isobutylene glycol,hexamethylene glycol, 2-ethylhexanediol, 2-chlo ro-2-met=hylpr-opanol-1,2-ethoxy-ethanol-1, 2-:b-utoxyethanol-l, mono-ethyl ether of diethyleneglycol, ethylene glycol mono-oleate, glyceryl mono-stearate, glyce-ryldipa-lmitate, Z-phenoxy-propandiol-1,3, benzyl alcohol, betaaphenethylalcohol, ally l alcohol, 4 buten-ol-l, Z-alpha-pyridyl-ethanoll,glycerol, 2-thioethoxy-ethanol 1, pentaerythritol, sorbitol, sorbitolmono-oleate, mannitol, mannitol dilaurate, ethanolarnine,diethanolamine, t-riethanolamine, propanolamine, commercial mixture of CC alcohols, betadisooctylphenoxy)ethanol,isooctylphenoxytetraethoxyethanol, 4-ketohexanol-l, 2,2-dihydroxy-diethylsul fide, etc. 'In most instances, the alcohol will bean unsubstituted monohydric or polyhydric aliphatic alcohol containingfrom 2 to about 24 carbon atoms such as n-butanol, diethylene glycol,oleyl alcohol, hexylene glycol, pentaerythritol, isooctanol,n-dodecanol, etc.

Me'rcaptans useful as this reagent include the various substituted andunsubstituted monoand poly-mercaptans containing LfI'OIII 2 \to or morecarbon atoms. Substituents which may be present in the mercaptansinclude groups such as chloro, lfl OI'O, hromo, nitro, nitroso, ether,sulfide, ester, keto, etc. Illustrative of mercaptans useful herein areethyl, n-propyl, ally], methally-l, n-butyl,

chlorobutyl, isooctyl, lauryl, cetyl, tricosyl, triacon-tyl,cyclo'hexyl, ethylcyclohexyl, phenyl, chlorophenyl, nitrophenyl,naphtlhyl, Ibenzyl, chloro benzyl, etc., mercaptans; propan=dithiol-1,3,hexandiflhiol |1,6, ethanol-l-thiol-Z, propandiol-1,2-thiol-3, hutylthiolactate, die-thyl mercaptosuccinate, Z-ethoxy-ethanthiol-l,3-thioethoxy-propan-- thiol-l, octantrithiol-l, 4,'8,2,3-diphenoxy-propanthiol-1, and Z-phenoxy-propanthiol-1,3. In mostinstances, the mercaptan will be an aliphatic mercaptan containing fromabout 2 to about 20 carbon atoms, especially an alkyl mercaptan such astertiary-butyl inercaptan, tertiary-octyl mercaptan, lauryl mercaptan,etc.

Amines useful as this reagent include any of the various primary,secondary, and tertiary monoarnines and polyamines containing from 2 to30 or more carbon atoms, Which amines may also contain substituents suchas chloro, fiuoro, brom-o, nitro, nitroso, ether, ester, sulfide, etc.Examples of such amines include ethylamine, d-iethylamine,triethylamine, n-butylamine, isobutylamine, 6-chloro-n-hexylarnine,tertiary-.octyl primary amine, tertiary-dodecyl primary amine,tertiary-octadecyl primary amine, docosy-lamine, hexacosylamine,triacontylamine, heXatriacontyla-mine, aniline, alpha-naphthylamine, N-methylanil-ine, N,N-d-iethyl aniline, ring alkylated anilines such asortho, meta, and para-toluidine, para-xylidine, ardodecyl aniline, etc.,pyridine and alkylated pyridines, piperazine, 'aminoethy-l piperazine,quinoline, pyrimidine, morpholine, oxazines, thiazines, ethylenediamine, diethlyene triamine, triet-hylene tetramine, tetraethylenepentamine, pentaethylene hexamine, commercial mixtures of ethylenepolyamines having an average molecular weight corresponding totetraethylene pentamine, propylene diamine, hexamethylene diamine,-N-hydroxyethyl-su sti-tuted mono-tertiary-dodecyl primary amine,commercial mixture of C C tentiary-alkyl primary amines having anaverage molecular Weight of about 191, cyclohexylamine,dicyclohexylamine, allylamine, methallylamine, isooctenylamine,Z-butoxyethylamine, aminoethyl olea-te, .aminopr-opyl stearate,bis-(dimethylaminopropyl) amine, N-aminopropyl-ootadecylamine,taminomethane, etc. In most instances, the amine will be an aliphaticamine of from '2 to about 20 carbon atoms which contains 1 to 5 aminogroups such as tertiary-butyl primary amine, tertiary-dodecyl primaryamine, trie-thylene tetraamine, tetraethylene pentamine, etc., or anaromatic amine such as pyridine, alpha-picoline, aniline, ar-dodecylaniline, quinoline, and the like.

Also useful as reagent C are amides and thioam-ides having from 1 to ormore carbon atoms which may contain substituents such as chloro, bromo,fluoro, nitro, nitroso, ether, sulfide, ester, etc., as well ashydrocarbon substituents on the amido nitrogen atom. Examples of suchamides and thioamides include urea and N-talkylated ureas, thiourea andN-alkylated thioureas, acetamide, thioacetamide, lbutyramide,caproamide, caprylamide, oleamide, stearamide, N,N-dimethy1 stearamide,hexacosanoic acid amide, triacontanoic acid amide, carnaubic acid amide,4-chloro butyramide, ibenzam-ide, thiobenzamide, N-lauryl benzamide,nitrobenzamide, the amides of petroleum naphthenic acids, cyclohexanecarboxylic acid amides, alphamaphthoic acid amide, adipamide,acry-lamide, methacrylamide, sebacic acid amide, succinamide,polyisobutene-substituted succinamide wherein the polyisobu-tenesubstituent contains from 12 to: 120 or more carbon atoms, commercialpolyamides known as Versamids derived from high molecular weightaliphatic dicarboxylic acids and ethylene polyamines,orthophthaldi-amide, ortho-phthalamid acid, lauryl orthophalamate,succina'mic acid, n-octyl succinamate, etc. In most instances, the amidewill be :an aliphatic amide. It is also possible and even desirable forcertain applications to employ an acylated amide or thioamide, i.e., animide, in lieu of or in partial replacement of the abovedescnibed amidesand thioamides. Thus, it is contemplated that the terms amide andthioamide used in the present specification and claims be inclusive ofamides and thioimides. Examples of useful limides and thioamides areltertiary-dodecyl succinimide, ortho-phthalimide, N- dodecylortho-phthalimide, maleimide, tertiary-dodecyl thiosuccinirnide,polyisobutene-substituted succinimide wherein the polyisobutenesubsti-tuent contains from about 50 to about 120 carbon atoms, etc.

For certain applications, it has also been found that mixtures of any ofthe foregoing reagent C materials with an alkylphenol are useful in theprocess of this invention. When such mixtures are used, it is generallydesirable to have present therein from about 0.1 to about moles of analkylphenol per mole of reagent C. Suoh alkylphenol may be a mono-alkylor a poly-alkyl phenol. The alkyl groups may he of any size, rangingfrom methyl up to alkyl groups derived from olefin polymers havingmolecular weights as high as 50,000 or more. Preferably the alkylphenolis a mono-alkylphenol in which the .alkyl group contains from 1 to aboutcarbon atoms, generally at least about 4 carbon atoms. Typical examplesof useful alkylphenols include, e.g., ortho, meta, and para-cresols;ortho, meta, and para-ethylpheno'ls; paraisopropylphenols, para-tertiarybutylphenol, ortho-n-amylphenol, para-tertiary amylphenol, heptylphenol,diisobutylphenol, n-decylphenol, wax-alkylated alpha-naphthol,wax-alkylated phenol, and polyisobutene-substituted phenol in which thepolyisobutene substituent contains from about 12 to about 76 carbonatoms. The alkylphenol may also contain substituent groups such aschloro, fluoro, nitro, nitroso, alkoxy, sulfide, ether, ester, etc. Alsouseful are polyhydric phenols such as alkyl- Iated resorcinols,alkylated catechols, alkylated pyrogallols, and their substitutionproducts.

The process for the formation of the organic phosphate complex of thisinvention may be carried out in any-one of several ways. For example,reagents A, B, C, and, optionally, an alkylphenol and an inert solvent,may be placed in a reaction vessel and then heated and stirred at atemperature within the range from about 50 C. to about 300 C.,preferably from about 80 C. to about 175 C., until the reaction iscomplete, which may require anywhere from 0.5 to 20 hours or more,depending on the particular reagents selected, the amount of suchreagents, the reaction temperature employed, etc. In other instances, itis preferable to place reagent B and, optionally, an inert solvent inthe reaction vessel, elevate the temperature to, say, 80 0, add reagentsA, C, and, optionally, an alkylphenol, and then beat the whole in themanner set forth above. Still another method is to disperse reagent A ina suitable inert solvent, add reagents B, C, and, optionally, analkylphenol, and then heat the whole in the described manner. It isnecessary only that all the reagents be contacted within the desiredtemperature range, and whether the reagents be added simultaneously orsuccessively, or the step of heating be carried out during or after themixing of the reagents, appears to be of no consequence.

Generally it is most convenient to conduct the process of this inventionin the presence of an inert, volatile solvent which serves to reduce theviscosity of the reaction mass. The solvent may remain in the finalproduct, if desired, to facilitate its application to metal surfaces.Any of the solvents ordinarily employed in the paint and varnishindustry may be used for the purpose such as benzene, xylene, toluene,mesitylene, cyclohexane, methylcyclohexane, aromatic petroleum spirits,chlorobenzene, trichloroethylene, ethylene dichloride, dioxane,turpentine, diisopropyl ether, and the like. Mixtures of one or more ofthe foregoing may also be used. In some instances, however, it ispreferred to conduct the process in the absence of the solvent and then,optionally, to dilute the organic phosphate complex with the desiredsolvent or mixture of solvents prior to its application to a metalsurface. This is generally the most advantageous and economicalprocedure in instances where the organic phosphate complex is to beshipped to some distant point.

Generally, some water is evolved during the process of this invention.This is removed simply and conveniently by venting the reaction vesselto the atmosphere or, in cases where an inert solvent is employed, byazeotropic distillation or azeotropic reflux.

The precise chemical composition of the organic phosphate complexes ofthis invention is not known. It is believed, however, that thephosphorus-containing reagent phosphorylates the organic hydroxycompounds and any mercapto compounds present to form acid phosphateester groups. Other reactions such as polymerization, salt formation,and/or etherification may also occur during the process and it is notintended that the theories presented herein be interpreted in any mannerwhich would limit the scope of the invention, except as defined by theappended claims.

The following examples are presented to illustrate specific modes ofcarrying out the process of this invention. The strong acid numberreported for the organic phosphate complex is determined according toASTM procedure D974-55T, except that bromphenol blue is used as the endpoint indicator. Unless otherwise indicated, all parts and percentagesare by weight.

Example 1 721 grams of xylene solvent and 575 grams (0.5 mole) of PolyolX-450 are introduced into a flask fitted with a reflux condenser and aside-arm water-trap. The whole is heated to C. over a 20-minute periodand then 89 grams 1.2 moles) of n-butanol and 57 grams (0.4 mole) ofphosphorus pentoxide are added. Thereafter the reaction mass is refluxedfor about 6 hours at 136 C. and 8 grams of water is observed to collectin the Water-trap. The product in the flask, a 50 percent solution ofthe desired organic phosphate complex in xylene solvent, shows thefollowing analyses.

Phosphorus, percent 1.69 Strong acid No. 32

Example 2 871 grams of xylene solvent and 575 grams (0.5 mole) of PolyolX-450 are introduced into a reaction vessel fitted with a refluxcondenser and a side-arm water-trap. The whole is heated to 120 C. andthen 239 grams (1.2 moles) of a commercial mixture of C -C aliphaticalcohols and 57 grams (0.4 mole) of phosphorus pentoxide are added at80100 C. Thereafter, the reaction mass is refluxed for 5.5 hours at C.while 11.5 grams of water is observed to collect in the side-armwater-trap. The product in the flask, a 50 percent solution of thedesired organic phosphate complex in xylene, shows the followinganalyses.

Phosphorus, percent 1.44 Strong acid No 26 Example 3 In a manner likeset forth in Example 2, 919 grams of xylene solvent, 575 grams (0.5mole) of Polyol X-450, 287 grams (1.2 moles) of a commercial mixture ofC C aliphatic alcohols, and 57 grams (0.4 mole) of phosphorus pentoxidereact to form an organic phosphate complex. During the reflux period,14.5 grams of water'is observed to collect in the side-arm water-trap.The product, a 50 percent solution of the desired organic phosphatecomplex in xylene solvent, shows the following analyses.

Phosphorus, percent 1.38 Strong acid No 24 Example 4 In a manner likethat set forth in Example 2, 954 grams of xylene solvent, 575 grams (0.5mole) of Polyol X-450, 322 grams (1.2 moles) of oleyl alcohol, and 57Phosphorus, per-cent 1.28 Strong acid No 23 Example Phosphorus, percent1.35 Strong acid No 29 Example 6 In a manner like that that set forth inExample 2, 696 grams of xylene solvent, 575 grams (0.5 mole) of PolyolX450, 64 grams (6.0 mole) of diet-hylene glycol, and 57 grams (0.4 mole)of phosphorus pentoxide react to form an organic phosphate complex.During the reflux period, grams of water is observed to collect in theside-arm water-trap. The product, a 50% solution of the desired organicphosphate complex in xylene, is filtered through cloth for the purposeof purification. The filtered product shows the following analyses.

Phosphorus, percent 1.23 Strong acid No 30 Example 7 In a manner likethat set forth in Example 2, 703 grams of xylene solvent, 575 grams (0.5mole) of Polyol X450, 71 grams (0.6 mole) of hexylene glycol, and 57grams (0.4 mole) of phosphorus pentoxide react to form an organicphosphate complex. During the reflux period 33 grams of water isobserved to collect in the side-arm water-trap. The product, a 50percent solution of a dark amber organic phosphate complex in xylenesolvent, shows the following analyses.

Phosphorus, percent 1.76 Strong acid No 38 Example 8 In a manner likethat set forth in Example 2, 721 grams of xylene solvent, 575 grams (0.5mole) of Polyol X-450, 89 grams (0.6 mole) of1,4-cyclohexane-dimethanol, and 57 grams (0.4 mole) of phosphoruspentoxide react to form an organic phosphate complex. During the refluxperiod, 12 grams of water collects in the side-arm watertrap. Theproduct, a 50 percent solution of an amber organic phosphate complex inxylene solvent, is decanted from a small amount of a brown resin in thebottom of the reaction vessel. It shows the following analyses.

Phosphorus, percent 0.77 Strong acid No 16 Example 9 702 grams of xylenesolvent, 431 grams (0.375 mole) of Polyol X-450, and 17 grams (0.125mole) of pentaerythritol are heated to 97 C. in a reaction vessel fittedwith a reflux condenser and a side arm water trap. Thereafter, 197 grams(1.2 moles) of para-tertiary amylphenol and 57 grams (0.4 mole) ofphosphorus pentoxide are added in the stated order to the reaction massat 70-100 C. The whole is refluxed for 6.5 hours at 145 C. while 14grams of water is removed from the side-arm water-trap. The product, a50 percent solution of the desired organic phosphate complex in xylenesolvent, is decanted from a small amount of a brown resin in the bottomof the reaction vessel. The product shows the following analyses.

Phosphorous, percent 1.32 Strong acid No. 25

Example 10 In a manner like that set forth in Example 9, 576 grams ofxylene solvent, 288 grams (0.25 mole) of Polyol X-450, 34 grams (0.25mole) of pentaerythritol, 197 grams (1.2 moles) of para-tertiaryamylphenol, and 57 grams (0.4 mole) of phosphorus pentoxide react toform an organic phosphate complex. During the reflux period, 10.5 gramsof water is removed from the side-arm watertrap. The product, an amber,fluid, organic phosphate complex containing 50 percent xylene solvent,is decanted from :a few grams of a hard resin which settles to thebottom of the reaction vessel. The product shows the following analyses.

Phosphorous, percent 1.41 Strong acid No. 27

Example 1] In .a manner like that set forth in Example 9, 1890 grams ofxylene solvent, 1150 grams (1.0 mole) of Polyol X-450, 34 grams (0.25mole) of pentaerythritol, 492 grams (3 moles) of para-tertiaryamylphenol, and 222 grams (1.56 moles) of phosphorous pentoxide react toform an organic phosphate complex of the present invention. During thereflux period, 31 grams of Water is removed from the side-armwater-trap. The product, a 47.5 percent solution of the desired organicphosphate complex in xylene, is filtered for the purpose ofpurification. The filtered product shows the following analyses.

Phosphorus, percent 2.0 Strong acid No. 35

Phosphorus, percent 1.41

Strong acid No 27 Example 13 1364 grams of xylene solvent and 575 grams0.5 mole) of Polyol X-450 are introduced into a reaction vessel fittedwith a reflux condenser and a side-arm water-trap. The whole is heatedto 100110- C. and then 732 grams (1.2 moles) of a commercial grade ofisooctylphenoxypolyethoxyethanol known under the trade designationTriton X- and 57 grams (0.4 mole) of phosphorus pentoxide are introducedinto the reaction vessel in the stated order at 74100 C. The whole isrefluxed for 6 hours at 143 C. while 8 grams of water is removed fromthe water-trap. The product, a 50 percent solution of the desiredorganic phosphate complex in xylene solvent, is an amber liquid whichshows the following analyses.

Phosphorus, percent 0.89 Strong acid No. 17

Example 14 In a manner like that set forth in Example 13, 807 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, grams 1.2 moles)of tertiaryoctyl mercaptan, and 57 grams (0.4 mole) of phosphoruspentoxide react to form an organic phosphate complex. During the refluxperiod, 11 grams of water is collected in the side-arm water-trap. Theproduct, a 50 percent solution of the desired organic phosphate complexin xylene solvent, is an amber, somewhat vicous liquid which shows thefollowing analyses.

Phosphorus, percent 1.48 Sulfur, percent 1.69 Strong acid No 28 Example15 In a manner like that set forth in Example 13, 720 grams of xylenesolvent, 575 grams (0.5 mole) of Polyol X-450, 88 grams (1.2 moles) oftertiarybutylamine, and 57 grams (0.4 mole) of phosphorus pentoxidereact to form an organic phosphate complex of this invention. During thereflux period, no water is evolved from the reaction mass. Upon cooling,the reaction mass deposits a small amount of white crystals, from whichthe liquid product is removed by decantation. 329 grams of isobutanolsolvent is added to (the decanted liquid product. The organic phosphatecomplex thus obtained is a clear yellow fluid containing 18.6 percentisobutanol solvent and 40.7 percent xylene solvent, It shows thefollowing analyses.

Phosphorus, percent 0.49

Nitrogen, percent 0.40

Strong acid No.

Example 16 1078 grams of xylene solvent and 720 grams (0.625 mole) ofPolyol X-450 are introduced into a reaction vessel fitted with a refluxcondenser and a side-arm watertrap. The whole is heated to 80 C. andthen 287 grams (1.5 moles) of a commercial mixture of C -C tertiaryalkylprimary amines having an average molecular weight of 191 and 71 grams(0.5 mole) of phosphorus pentoxide are added in the stated order at 6080C. The whole is refluxed for 4 hours at. 145 C. while 1.6 grams of wateris observed to collect in the side-arm water-trap. The product, a 50percent solution of the desired organic phosphate complex in xylenesolvent, is a clear, yellow-orange viscous liquid showing the followinganalysis.

Phosphorus, percent 1.25 Nitrogen, percent 0.78 Strong acid No 18Example 17 In a manner like that set forth in Example 13, 1143 grams ofxylene solvent, 720 grams (0.625 mole) of Polyol X450, 352 grams (1.5mole) of a technical grade of N-monohydroxyethyl-tertiary-dodecylprimary amine, and. 71 grams (0.5 mole) of phosphorus pentoxide react toform an organic phosphate complex of the present invention. During thereflux period, 4.2 grams of water is observed to collect in the side-armwater-trap. The product, a 50 percent solution of the desired organicphosphate complex in xylene solvent, is a clear, yellow, somewhatviscous liquid showing the following analyses.

Phosphorus, percent 1.31 Nitrogen, percent 0.82 Strong acid No 11Example 18 10. product, a 50 .percent solution of the desired organicphosphate complex in xylene solvent, is. a light amber, viscous liquidshowing the following analyses.

Phosphorus, percent 1.45-

Nitrogen, percent 0.53

Strong acid N0 5 Example 19 In a manner like that set forth in Example18, 837 grams of xylene solvent, 575 grams (0.5 mole) of Polyol X-450,148 grams (0.9 mole) of para-tertiary amylphenol, 57 grams (0.3 mole) ofthe commercial primary amine mixture described in Example 18, and 57grams 0.4 mole) of phosphorus pentoxide react to form an organicphosphate complex of the present invention. During the reflux period, 4grams of water is collected in the side-arm Water-trap. The product, a50 percent solution of the desired organic phosphate complex in xylene,is an amber, somewhat viscous liquid showing the following analyses.

Phosphorus, percent 1.48 Nitrogen, percent 0.26 Strong acid No. 16

Example 20 In a manner like that set forth in Example 13, 683 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, 51 grams (0.24average mole) of a commercial mixture of ethylene polyamines containing33.4 percent nitrogen and having a composition corresponding to that oftetraethylene pentamine, and 57 grams (0.4 mole) of phosphorus pentoxidereact to form anorganic phosphate complex. During the 7-hour refluxperiod, 2 grams of water is observed to collect in the side-armwater-trap. The crude product is decanted from a small amount of anorange residue in the reaction vessel and the decanted liquid is blendedwith 155 grams of isobutanol solvent. The product, an organic phosphatecomplex which contains 10.2 percent isobutanol solvent and 44.9 percentxylene solvent, is a viscous liquid which shows the following analyses.

Phosphorus, percent 1.61 Nitrogen, percent 0.99 Strong acid No. 1(basic) Example 21 727 grams of xylene solvent and 575 grams 0.5 mole)of Polyol X-450 are introduced into a reaction vessel fitted with areflux condenser and a side-arm water-trap. The whole is heated to 120C. and then grams 1.2 moles) of pyridine and 57 grams (0.4 mole) ofphosphorus pentoxide are added in the stated order at 83 95 C.Thereafter, the reaction mass is refluxed for 5.25 hours, while 1 gramof water is collected in the side-arm water-trap. The desired organicphosphate complex is filtered from a tan crystalline by-product. Thefiltered product, which contains approximately 50 percent xylenesolvent, is a clear yellow liquid showing the following analyses.

Phosphorus, percent 0.23 Nitrogen, percent 0.65

Example 22 In a manner like that set forth in Example 13, 744

The crude product is.

1 1 Example 23 794 grams of xylene solvent and 546 grams (0.475 mole) ofPolyol X-450 are introduced into a reaction vessel fitted with a refluxcondenser and a side-arm watertrap. The whole is heated to 100 C. andthen 194 grams (1.14 average moles) of a commercial mixture of loweralkylated pyridines consisting principally of xylidines and toluidines,and 54 grams (0.38 mole) of phosphorus pentoxide are added in the statedorder at 5270 C. Thereafter, the reaction mixture is refluxed for 5.5hours and 3 grams of water is observed to collect in the sidearmwater-trap. The crude product is decanted from a small amount of solidmaterial on the bottom of the flask and filtered through cloth forpurposes of purification. The filtered product, a 50 percent solution ofthe desired organic phosphate complex in xylene solvent, is a clear,dark-amber liquid showing the following analyses.

Phosphorus, percent 0.22

Nitrogen, percent 0.71

Strong acid No. 4

Example 24 In a manner like that set forth in Example 13, 777 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, 145 grams (1.2moles) of 2-methyl-5-ethyl-pyridine, and 57 grams (0.4 mole) ofphosphorus pentoxide react to form an organic phosphate complex of thisinvention. During the reflux period, 1.6 grams of water is collected inthe side-arm water-trap. The product, which is decanted from a smallamount of solid in the reaction vessel, contains approximately 50percent xylene solvent and is a yellow, slightly cloudy fluid showingthe following analyses.

Phosphorus, percent 0.3 Nitrogen, percent 0.41 Strong acid No.

Example 25 In a manner like that set forth in Example 18, 831 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, 148 grams (0.9mole) of paratertiary amylphenol, 51 grams (0.3 mole) of a commercialmixture of lower alkylated pyridines consisting principally of xylidinesand toluidines, and 57 grams (0.4 mole) of phosphorus pentoxide react toform an organic phosphate complex of the present invention. During therefiux period, 4 grams of water is observed to collect in the side-armwater-trap. The product is decanted from a small amount of a brownresidue which collects in the bottom of the reaction vessel. Thedecanted material, a percent solution of the desired organic phosphatecomplex in xylene solvent, is an amber fluid having the followinganalyses.

Phosphorus, percent 0.98 Nitrogen, percent 0.16 Strong actid No. 16

Example 26 sired organic phosphate complex in xylene solvent, is anamber fluid showing the following analysis.

Phosphorus, percent 0.16 Nitrogen, percent 0.76 Strong acid No. 3

1 2 Example 27 In manner like that set forth in Example 13, 946 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, 314 grams (1.2moles) of ar-dodecyl aniline, and 57 grams (0.4 mole) of phosphoruspentoxide react to form an organic phosphate complex. During the refluxperiod, 6 grams of Water is collected in the side-arm water-trap. Theproduct, a 50 percent solution of the desired organic phosphate complexin xylene solvent, is a dark-amber, slightly viscous liquid showing thefollowing analyses.

Phosphorus, percent 1.29 Nitrogen, percent 0.81 Strong acid No. 28

Example 28 In a manner like that set forth in Example 13, 969 grams ofxylene solvent, 575 grams (0.5 mole) of Polyol X-450, 337 grams (1.2moles) of a technical grade of oleamide, and 57 grams (0.4 mole) ofphosphorus pentoxide react to form an organic phosphate complex. Duringthe reflux period, 5.5 grams of water is observed to collect in theside-arm water-trap. The crude product is filtered through cloth forpurposes of purification. The filtrate, a 50 percent solution of thedesired organic phosphate complex in xylene solvent, is an amber liquidshowing the following analyses.

Phosphorus, percent 0.74 Nitrogen, percent 0.47 Strong acid No. 4

' Example 29 965 grams of xylene solvent and 575 grams (0.5 mole) ofPolyol X-450 are introduced into a reaction vessel fitted with a refluxcondenser and a side-arm water-trap. The whole is heated to about C. and147 grams (0.9 mole) of para-tertiary amylphenol is added rapidlythereto at 71-82 C. While the whole is stirred at about 80 C., 186 gramsof a polyamide derived from a high molecular weight aliphaticdicarboxylic acid and ethylene polyamines (known under the tradedesignation Versamid-IOO) is added slowly over a period of about 2 hoursat 60-74 C. Thereafter 57 grams (0.4 mole) of phosphorus pentoxide isadded over a 5-minute period at 7479 C. The reaction mass becomes veryviscous, so an addition of 965 grams of xylene solvent is made tofacilitate azeotropic reflux. The whole is then refluxed for 3 hoursWhile 0.6 gram of water is collected in the side-arm water-trap. Theproduct, a 33.3 percent solution of the deisred organic phosphatecomplex in xylene solvent, shows the following analyses.

Phosphorus, percent 0.88 Nitrogen, percent 0.42 Strong acid No. 1(basic)Example 30 In a manner like that set forth in Example 29, 1100 grams ofxylene solvent (2 portions of 834 and 266 grams, respectively), 575grams (0.5 mole) of Polyol X-450, 147 grams (0.9 mole) of para-tertiaryamylphenol, 55 grams of a polyamide derived from a high molecular weightaliphatic dicarboxylic acid and ethylene polyamines (known under thetrade designation Versamidand 57 grams (0.4 mole) of phosphoruspentoxide react to form an organic phosphate complex of the presentinvention. During the reflux period, 3.2 grams of water is collected inthe side-arm water-trap. The prod- I uct, a 43 percent solution of thedesired organic phosphate complex in xylene solvent, is an amber,somewhat viscous liquid showing the following analyses.

Phosphorus, percent 1.26 Nitrogen, percent 0.37 Strong acid No. 9

13 Example 31 980 grams of xylene solvent and 575 grams (0.5 mole) ofPolyol X-450 are introduced into a reaction vessel fitted with a refluxcondenser and a side-arm water-trap. While the whole is heated to 120C., 348 grams (0.6 mole) of N,N'-diootadecyl-thiourea, and 57 grams (0.4mole) of phosphorus pentoxide are added in the stated order at 103120 C.Thereafter, the whole is refluxed for 6 hours while 2.5 grams of Wateris observed to collect in the side-arm water-trap. Upon cooling, thereaction mass is diluted with 1230 milliliters of isobutanol solvent and500 milliliters of methyl isobutyl ketone solvent. For purposes ofinvestigation, all the solvents were removed from the organic phosphatecomplex in this experiment. The solvent-free organic phosphate complexis a light-brown amorphous solid which shows the following analyses.

Phosphorus, percent 2.50 Nitrogen, percent 1.70 Strong acid No.

Example 32 In the same manner set forth in Example 13, 1,393 grams ofxylene, 1,150 grams (1.0 mole) of Polyol X-450, 129 grams (0.68 mole) ofa commercial mixture of C C tertiary-alkyl primary amines having anaverage molecular weight of about 191, and 114 grams (0.8 mole) ofphosphorus pentoxide react to form an organic phosphate complex. Duringthe reflux period, 7 grams of water is collected in the side-armwater-trap. The crude product is then stirred for 3 hours at 35 C. with697 grams of isobu-tanol solvent.

The product, a solution of the desired organic phosphate complexcontaining 40% of xylene solvent and of isobutanol solvent, is a clear,orange liquid showing the following analyses.

Phosphorus, percent 1.39 Nitrogen, percent 0.28 Strong acid No. 12

A number of laboratory and outdoor exposure tests were carried out todetermine the utility of the hereindescribed organic phosphate complexesas protective coating compositions per se for metals, as primers toprepare a metal article to receive a top-coat of a siccative organiccoating composition such as paint, varnish, lacquer, primers, syntheticresins, enamel, etc., and as improving agents in such siccative organiccoating compositions. They are also useful as improving agents inwater-base or emulsion paints such as synthetic latex paints derivedfrom acrylic resins, polyvinyl alcohol resins, alkyd resins, etc., byemulsification thereof with water, as well as in water-soluble paints orprimers derived from water-soluble alkyd resins, acrylic resins, and thelike. The complexes of this invention may be applied to metal surfacesby any one of the methods ordinarily used in the paint and varnishindustry such as brushing, spraying, dip-coating, flow-coating,roller-coating, and the like. The viscosity of the complex or thecoating composition containing the complex may be adjusted for theparticular method of application selected by adding a suitable amount ofa solvent such as benzene, xylene, mesitylene, aromatic petroleumspirits, turpentine, or other appropriate solvents. The metal surfacewhich has been thus coated is then dried either by exposure to air or bymeans of a baking procedure. A dry film thickness of the complex or thecoating composition containing the same ranging from about 0.01 mil toabout 4 mils, preferably 0.02-2 mils, is usually required to provideadequate protection for the metal surface. Coatings heavier than 4 milscan be used, if desired, but they normally contribute little in the wayof additional protection. In some instances, it is desirable to admixthe complex with a pigment such as titanium dioxide, chrome green,aluminum powder, carbon black, iron oxide, or Zinc chromate. In someinstances, it is also desirable to include conventional improving agentssuch as pigment extenders, anti-skinning agents, driers, gloss agents,color stabilizers, etc.

Example A A number of 4-inch by 8-inch panels of clean, 20- gaugecold-rolled SAE 1020 steel were dip-coated, respectively, with a good,commercial, air-dry clear alkyd primer and several complexes of thisinvention. Thereafter, each primed panel was air-dried for two days (dryfilm measured 0.1i0.01 mil), dip-coated with a commercial, white alkydenamel, and baked in an oven for 20 minutes at 275 F. The film of bakedenamel measured 1:0.1 mil.

The primed and top-coated panels were then subjected to a waterimmersion test. In this test, the panels are completely immersed for 16hours in a water bath maintained at 160 F. Upon removal from the bath,each panel was rated for coating adhesion on a scale of 0 to 100, 100representing a perfect panel free from blisters and/or flaking and 0representing a completely blistered and/or flaked panel.

The results obtained in this test are set forth in Table I.

TABLE I.WATER IMMERSION TEST Primer used under enamel top-coat: Coatingadhesion value Commercial alkyd primer (control) 44 Product of Example14 100 Product of Example 1 Product of Example 32 It will be noted thatthe complexes of this invention were superior to a known primer inimproving the adhesion of an enamel to a ferrous surface.

Example B A number of primed and top-coated panels were prepared in themanner set forth in Example A and then subjected to the water immersiontest described in that example. Upon removal from the bath, each panelwas cross-hatched with a pointed steel instrument by making elevenparallel, one-inch long scribes spaced inch apart and a similar numberof intersecting scribes at right angles thereto. Adhesive cellophanetape was then applied to the scribed area and removed. The scribed areawas rated for coating adhesion on a scale of 0 to 10, 10 representing aperfect panel showing no loss of the coating and 0 representing a panelwhich lost all of the coating in the cross-hatched area.

The results observed in this test are shown in Table II.

TABLE II.CROSS-HATCH ADHESION TEST (AFTER WATER IMMERSION) Primer usedunder enamel Cross-hatch top-coat: adhesion value Commercial alkydprimer (control) 0 Product of Example 14 2 Product of Example 1 9Product of Example 32 10 Again, the complexes of this invention weremore effective than a known primer in promoting the adhesion of anenamel to a ferrous surface.

Example C A number of 4-inch by 8-inch panels of clean, 20- gaugecold-rolled SAE 1020 steel were primed, respectively, with a commercial,clear alkyd primer and several complexes of this invention and allowedto air-dry for two days. The film thickness on each panel was found tobe 01:0.01 ml.

The primed panels were then placed in a rack at a 45 angle and storedoutdoors in the Great Lakes region for TABLE III.-OUTDOOR EXPOSURE TEST(ONE WEEK) Primer coat on panel: Inspectors remarks Commercial alkydprimer (control) Heavy rusting on edges; scattered rust spots on weatherface. Product of Example 14 No edge rust; a few rust spots on weatherface. Product of Example 1 No rust; weather face slightly discolored.Product of Example 32 No edge rust; a few rust spots on weather face.

It will be noted that the complexes of this invention are useful per seas clear film primers for metal surfaces. They are more effective forthis purpose than a known, clear film primer.

Example D A number of primed and tp-coated steel panels were prepared inthe same manner set forth in Example A, except that a commercial,amine-modified alkyd white enamel was used as the top-coat material andthe baking schedule was 20 minutes at 400 F.

The primed and top-coated panels were subjected to a salt fog corrosiontest for 100 hours. The apparatus used for this test is described inASTM procedure B 117-57T. It consists of a chamber in which a mist orfog of 5 percent aqueous sodium chloride solution is maintained incontact with the test panels at 95i2 F. The panels in this instance wereremoved from the chamber after 100 hours, washed with water, and scrapedvigorously with a putty knife to remove any coating which had loosened.Each panel was inspected to determine the percent of the total areathereof which was still covered with an adherent coating (reported aspercent of coating adhered). The results are shown in Table IV.

TABLE IV.SALT FOG CORROSION TEST, 100 HOURS It will be noted that thecomplexes of this invention were more effective than a known primer inimproving the adhesion of an enamel top-coat to a metal surface in ahighly corrosive environment.

Example E A commercial white enamel was milled from 400.3 parts ofpigment grade titanium dioxide, 713.9 parts of a commercial alkyd resin(60% non-volatiles), 1.5 parts of a commercial cobalt naph-thenate drier(6% cobalt content), 232.8 parts of aromatic petroleum spirits, and 22.5parts of varnishmakers naphtha.

A similar group of enamels was compounded, differing only in that 7percent of the alkyd resin (i.e., 50 parts thereof) was replaced,respectively, by 50 parts of a number of different complexes of thisinvention.

Steel panels of the type previously described were dipped, respectively,in the commercial white enamel and the experimental enamels containingorganic phosphate complexes of this invention, then baked for 20 minutesat 275 F. The top-coated panels were subjected to the water immersiontest described in Example A. Another similarly prepared set of panelswas subjected to the cross-hatch adhesion test described in Example B.The results obtained in each of the tests are shown in Table V.

TABLE V.WATER IMMERSION AND CROSS-HATCH ADHESION TESTS Water Cross-HatchEnamel Used To Provide Coating For Immersion Adhesion Steel PanelAdhesion Value Value Commercial white enamel (control) 18 0 Enamelcontaining the product of Example 2O 10 Enamel containing the product ofExample 14 53 1 Enamel containing the product of Examp 100 10 Enamelcontaining the product of Exam- 87 9 p Enamel containing the product ofExamp 66 10 Enamel containing the product of Example 32 77 10 Enamelcontaining the product of Example 30 67 4 It will be noted that thecomplexes of this invention are effective as additives in a knownsiccative organic coating composition for the purpose of improvingadhesion.

Example F A group of steel pane-ls prepared in the same manner set forthin Example E was subjected to the Olsen cup test. The test, whichmeasures the adhesion of a coating composition to a metal surface undersevere deformation conditions, consists of a device in which the coatedtest panel is securely clamped and then deformed. Access is provided :tothe panel through a one-inch diameter circular opening. Through thisopening, a /s-inch diameter rounded cylindrical piston is forced againstthe panel until the resulting dimple ruptures. The panel is then removedand pressure-sensitive tape is applied to the convex surface of thedimple. After removal of the tape, the convex surface of the dimple israted on a scale of 0 to 5, 5 indicating perfect adhesion and 0indicating a complete loss of the coating composition (i.e., noadhesion).

The results obtained in this test are shown in Table VI.

TABLE VI.OLSEN CUP TEST Enamel used to provide coating for steel panel:Olsen adhesion value Commercial white enamel (control) 3 Enamelcontaining the product of Example 20 5 Enamel containing the product ofExample 14 4 Enamel containing the product of Example 1 5 Enamelcontaining the product of Example 2 4 Enamel containing the product ofExample 6 4 Enamel containing the product of Example 32 4 Enamelcontaining the product of Example 30 4 It will be noted that thecomplexes of this invention are effective as additives in a knownsiccative organic coating composition for the purpose of improvingadhesion under severe conditions of deformation.

In addition to their utility as protective coating materials for ferrousmetals, the organic phosphate complexes of this invention are useful inprotecting nonferrous metals and alloys thereof such as aluminum,magnesium, copper, brass, bronze, white metal, etc., against corrosion.They are also useful as protective coating materials on galvanizedferrous surfaces, on plated metal surfaces such as copper-plated,nickel-plated, and cadmium-plated ferrous surfaces, and on phosphatedmetal surfaces. They are also useful as protective coating materials onchromated aluminum or chromated zinc surfaces, i.e., aluminum or zincsurfaces which have been treated with an aqueous solution of chromicacid and/or a derivative thereof such as a metal chromate or dichromate,an amine chromate, ammonium chromate, etc. Particularly fine results areobtained when the coating compositions of the present invention areapplied over a metal surface which has been phosphated by means of anovel aqueous phosphating solution containing as essential ingredientszinc ion, phosphate ion, nitrate ion, and a cation selected from thegroup consisting of lithium, beryllium, magnesium, calcium, strontium,cadmium, and barium. Such phosphating solutions, which provide a dense,adherent, micro-crystalline or amorphous phosphate coating upon themetal substrate, are described in detail in co-pending US. application,Ser. No. 373,449, filed August 10, 1953, now Patent No. 3,090,709,issued May 21, 1963. It is intended that the entire disclosure of Ser.No. 373,449 be incorporated herein by reference.

What is claimed is:

1. An organic phosphate complex prepared by the process which comprisesthe reaction of a mixture consisting essentially of:

(A) one mole of a phosphorus-containing reagent selected from the groupconsisting of phosphorus pentoxide and phosphoric acids,

(B) from about 0.2 to about 12.5 moles of a copolymer of allyl alcoholand a styrene, and

(C) from about 0.1 to about moles of a compound other than an epoxy arylether, said compound being selected from the group consisting ofalcohols, mercaptans, amines, amides, and thioamides,

at a temperature within the range from about 50 C. to about 300 C.

2. An organic phosphate complex prepared by the process which comprisesthe reaction of a mixture consisting essentially of:

(A) one mole of a phosphorus-containing reagent selected from the groupconsisting of phosphorus pentoxide and phosphoric acids,

(B) from about 0.2 to about 12.5 moles of a copolymer of allyl alcoholand a styrene,

(C) from about 0.1 to about 5 moles of a compound other than an epoxyaryl ether, said compound being selected from the group consisting ofalcohols, mercaptans, amines, amides, and thioamides, and

(D) from about 0.1 to about 20 moles of an alkylphenol per mole of (C),

at a temperature within the range from about 50 C. to about 300 C.

3. A complex in accordance with claim 1 characterized further in thatthe phosphorus-containing reagent of (A) is phosphorus pentoxide.

4. A complex in accordance with claim 1 characterized further in thatthe copolymer of (B) is a copolymer of about equimolar amounts of allylalcohol and styrene and has an average molecular weight in the rangefrom about 500 to about 5,000.

5. A complex in accordance with claim 1 characterized further in thatthe compound of (C) is a monohydric alcohol.

6. A complex in accordance with claim 3 characterized further in thatthe copolymer of (B) is a copolymer of about equimolar amounts of allylalcohol and styrene and has an average molecular weight in the rangefrom about 1100 to about 1150, and the compound of (C) is n-butanol.

7. A complex in accordance with claim 1 characterized further in thatthe compound of (C) is a polyhydric alcohol.

8. A complex in accordance with claim 3 characterized further in thatthe copolymer of (B) is a copolymer of about equimolar amounts of allylalcohol and styrene and has an average molecular weight in the rangefrom about 1100 to about 1150, and the compound of (C) is diethyleneglycol.

9. A complex in accordance with claim 1 characterized further in thatthe compound of (C) is an aliphatic mercaptan.

10. A complex in accordance with claim 3 characterized further in thatthe copolymer of (B) is a copolymer of about equimolar amounts of allylalcohol and styrene and has an average molecular weight in the rangefrom about 1100 to about 1150, and the compound of (C) is tertiary-octylmercaptan.

11. A complex in accordance with claim 1 characterized further in thatthe compound of (C) is an aliphatic amine.

12. A complex in accordance with claim 3 characterized further in thatthe copolymer of (B) is a copolymer of about equimolar amounts of allylalcohol and styrene and has an average molecular weight in the rangefrom about 1100 to about 1150, and the compound of (C) is a mixture of Cto C tertiary-alkyl primary amines having an average molecular weight ofabout 191.

13. A complex in accordance with claim 1 characterized further in thatthe compound of (C) is an aromatic amine.

14.A complex in accordance with claim 1 characterized further in thatthe compound of (C) is an aliphatic amide.

15. A metal article which has been protected against corrosion byapplying thereto a film comprising the complex of claim 1.

16. A metal article which has been protected against corrosion byapplying thereto a film which comprises a major proportion of asiccative organic coating composition and a minor proportion of thecomplex of claim 1.

References Cited by the Examiner UNITED STATES PATENTS 3,133,838 5/1964Higgins 1486.15

RICHARD D. NEVIUS, Primary Examiner.

R. S. KENDALL, Assistant Examiner.

1. AN ORGANIC PHOSPHATE COMPLEX PREPARED BY THE PROCESS WHICH COMPRISESTHE REACTION OF A MIXTURE CONSISTING ESSENTIALLY OF: (A) ONE MOLE OF APHOSPHORUS-CONTAINING REAGENT SELECTED FROM THE GROUP CONSISTING OFPHOSPHORUS PENTOXIDE AND PHOSPHORIC ACIDS, (B) FROM ABOUT 0.2 TO ABOUT12.5 MOLES OF A COPOLYMER OF ALLYL ALCOHOL AND A STYRENE, AND (C) FROMABOUT 0.1 TO ABOUT 5 MOLES OF A COMPOUND OTHER THAN AN EPOXY ARYL ETHER,SAID COMPOUND BEING SELECTED FROM THE GROUP CONSISTING OF ALCOHOLS,MERCAPTANS, AMINES, AMIDES, AND THIOAMIDES, AT A TEMPERATURE WITHIN THERANGE FROM ABOUT 50*C. TO ABOUT 300*C.
 16. A METAL ARTICLE WHICH HASBEEN PROTECTED AGAINST CORROSION BY APPLYING THERETO A FILM WHICHCOMPRISES A MAJOR PROPORTION OF A SICCATIVE ORGANIC COATING COMPOSITIONAND A MINOR PROPORTION OF THE COMPLEX OF CLAIM 1.